Multiway systems [emulation]
It is straightforward to emulate a k-color multiway system with a 2-color one, just by encoding successive colors by strings like "AAABBB"
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"AAABBB", "AAABAB"
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"AAABAB" and "AABABB"
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"AABABB" that have no overlaps. (Compare page 1033.)